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Jornais Acesso aberto

Michael Strubell, Victor Cunill, George Gibson, Peter S. Stevens, Gavin P. Murphy, O. W. Van Petten, W.N. Menzies-Wilson, Richard Layard, Rev. H. Vellacott, Paul Snell, N.C. Tapp, Rob Warden, A. Peter Ruderman, Alberto Quiroga, Dave Durenberger, Roy Pierce, Peter E. Sandor,

... pris Credit cards Libel Health care Labour shortages? Archaeopteryx Jobs for civil servants A bridge too early ...

1984 - Gale Group | The Economist

Artigo Acesso aberto Revisado por pares

Nicholas R. Longrich, Jakob Vinther, Qingjin Meng, Quangguo Li, Anthony P. Russell,

... assumed that wing feathers in the Jurassic bird Archaeopteryx [4Rietschel S. Feathers and wings of Archaeopteryx and the question of her flight ability.in: ... The Beginnings of Birds: Proceedings of the International Archaeopteryx Conference, Eichstätt, 1984. Freunde des Jura-Museums, Eichstätt, ... University Press, New Haven, CT1996Google Scholar, 6Wellnhofer P. Archaeopteryx: Der Urvogel von Solnhofen. Verlag Dr. Friedrich Pfeil, Munich2008Google Scholar, 7De Beer G.R. Archaeopteryx lithographica: A Study Based on the British Museum ...

Tópico(s): Amphibian and Reptile Biology

2012 - Elsevier BV | Current Biology

Jornais Acesso aberto

Chris Peachment, Alexandra Shulman, Robert Dawson Scott, Patricia Davies, Daniel Ward, Motor Industry Correspondent, Jane MacQuitty, Simon Barnes, Diana Wildman, Andrew Morgan, Cliff Feltham, Ivo Tennant, Andrei Navrozov, Michael Binyon, Noel Goodwin, Jeremy Flint, Richard Streeton, Colin Narbrough, Bernard Levin, Howard Foster, Francesca Greenoak, Bryan Stiles, Jim Railton, Robert Grieves Peking, Mitchell Platts, Golf Correspondent, Sarah Thompson, Education Reporter, Harry Golombek, Michael Tate, Norman Hammond, Archaeology Correspondent, Ruth Gledhill, Alan Webster, Lawrence Lever, John Woodcock Cricket Correspondent, David Bonavia, Peter Waymark, Pearson Phillips, Charles Jackson, Alan Hamilton, Robin Young, Jenny MacArthur, Sabine Durrant, Frances Bissell, Ian Bradley, Charles Bremner, Stuart Jones, Football Correspondent, Bruce Laughland, David Howell, John Hennessy, John Young, Agriculture Correspondent, Derek Nuttall, Director, Alex McWhirter, Harvey Elliott, Air Correspondent, Edward Fennell, Nicole Swengley, Gavin Bell, Robert Kirley, David Miller, Nigel Andrew, Philip Webster, Chief Political Correspondent, Geoffrey Wheeler, (Michael Phillips), Kerry Gill, Raymond Keene, Roy Hay, P. W., Ray Heath, S. M. T. Wasti, Paul Griffiths, Angela Wilkes, Peter Bryan, Kenneth Branagh, Martha Honey, John Blunsden, Martin Searby, Barry Pickthall, Peter Brimelow, Bryan Appleyard, Andrew Sanger, Robert Kilroy, Rodney Drake, Kenneth Fleet, Robert Green, Pat Butcher, Athletics Correspondent, Ian Smith, Philip Webster Chief Political Correspondent, G. E. Swain, Graham Searjeant, Financial Editor, Amanda Pardoe, David Gollob, Alan Lee, Peter Dear and Peter Davalle, Ian Stafford, David Sinclair, Tim Jones, Jonathan Meades, Bailey Morris, Robert Fisk, Rodney Lord, Economics Editor, Michael Evans Defence Correspondent, Jack Bailey, Jack Bell, Darryl Gibson, S. C. P., Colin Campbell, Horace B. Barlow, George J. Levy, Shona Crawford Poole, Judy Froshaug, David Fallows, Conal Gregory, Ray Whitney, Richard Ford, Michael Coleman, Mary Dejevsky, Richard Williams, Robert Harley,

... fossil is foundering as feathers look like fakes Archaeopteryx debate Rees in demand for MI5 inquiry Executive ...

1987 - Gale Group | TDA

Artigo Acesso aberto Revisado por pares

John H. Ostrom,

... birds can be equated with the origin of Archaeopteryx, the oldest known bird. Analysis of the five presently known skeletal specimens of Archaeopteryx. and comparison with the skeletal anatomy of the ... Holmgren (1955), namely, that the skeletal anatomy of Archaeopteryx is extraordinarily similar to that of contemporaneous and ... theropods, and on that basis suggested a common Archaeopteryx–dinosaur ancestry among pseudosuchian reptiles. That evidence is ... unique ischial morphology, virtually every skeletal feature of Archaeopteryx is known in several contemporaneous or near-contemporary ...

Tópico(s): Ichthyology and Marine Biology

1976 - Oxford University Press | Biological Journal of the Linnean Society

Artigo Acesso aberto Revisado por pares

Oliver W. M. Rauhut, Christian Foth, Helmut Tischlinger,

The iconic primeval bird Archaeopteryx was so far mainly known from the Altmühltal Formation (early Tithonian) of Bavaria, southern Germany, with one specimen having been ... new specimen, we discuss several problematic issues concerning Archaeopteryx, including the monophyly and diagnosis of the genus, ... Based on a new diagnosis for the genus Archaeopteryx, the Berlin, Eichstätt, Solnhofen, Munich, Daiting, Thermopolis, 11th, ... The Maxberg specimen is very probably also an Archaeopteryx, based on overall similarity, although none of the ...

Tópico(s): Pleistocene-Era Hominins and Archaeology

2018 - PeerJ, Inc. | PeerJ

Artigo Acesso aberto Revisado por pares

Gérald Mayr, Burkhard Pohl, Scott Hartman, Dieter Stefan Peters,

... complete and well-preserved skeleton is assigned to Archaeopteryx siemensii Dames, 1897 and provides significant new information ... evident from the new specimen, the palatine of Archaeopteryx was tetraradiate as in non-avian theropods, and ... of a previous reconstruction of the palate of Archaeopteryx. The morphology of the coracoid and that of ... the presence of a hyperextendible second toe in Archaeopteryx. This feature is otherwise known only from the ... deinonychosaurs (Dromaeosauridae and Troodontidae), and its presence in Archaeopteryx provides additional evidence for a close relationship between ...

Tópico(s): Ichthyology and Marine Biology

2007 - Oxford University Press | Zoological Journal of the Linnean Society

Artigo Acesso aberto

Zhonghe Zhou, Fucheng Zhang,

... with a complete long skeletal tail except for Archaeopteryx. Two newly discovered specimens referable to Jeholornis provide ... of Jeholornis is much longer than that of Archaeopteryx and comprises a maximum of 27 caudal vertebrae compared with only 23 in Archaeopteryx. More interestingly, the tail feathers are shaped more like those of dromaeosaurs than those of Archaeopteryx. We conclude that the common ancestor of birds ... have a more primitive tail than that in Archaeopteryx, confirming the side branch position of Archaeopteryx in ...

Tópico(s): Ichthyology and Marine Biology

2003 - Springer Science+Business Media | The Science of Nature

Artigo Acesso aberto Revisado por pares

Daniela Schwarz, Martin Kundrát, Helmut Tischlinger, Gareth J. Dyke, Ryan M. Carney,

The question of whether the iconic avialan Archaeopteryx was capable of active flapping flight or only passive gliding is still unresolved. This study contributes to this debate by reporting on two ... most of the vertebral column of the Berlin Archaeopteryx possesses intraosseous pneumaticity, and that pneumatic structures also ... the anterior thoracic vertebrae in other specimens of Archaeopteryx. With a minimum Pneumaticity Index (PI) of 0.39, Archaeopteryx had a much more lightweight skeleton than has ...

Tópico(s): Evolution and Paleontology Studies

2019 - Nature Portfolio | Scientific Reports

Artigo Revisado por pares

Martin Kundrát, John R. Nudds, Benjamin P. Kear, Junchang Lü, Per Ahlberg,

... as the oldest evolutionary prototype of a bird, Archaeopteryx has, as a result of recent fossil discoveries, ... group birds. This has prompted debate over whether Archaeopteryx is simply a convergently bird-like non-avialan ... genus, that the eighth or Daiting specimen of Archaeopteryx possesses a character suite that robustly constrains it ... enough to merit designation as a new species, Archaeopteryx albersdoerferi sp. nov., but is recovered in close phylogenetic proximity to Archaeopteryx lithographica. Skeletal innovations of the Daiting specimen, such ...

Tópico(s): Ichthyology and Marine Biology

2018 - Taylor & Francis | Historical Biology

Artigo Acesso aberto Revisado por pares

Michael S. Y. Lee, Trevor H. Worthy,

The widespread view that Archaeopteryx was a primitive (basal) bird has been recently challenged by a comprehensive phylogenetic analysis that placed Archaeopteryx with deinonychosaurian theropods. The new phylogeny suggested that ... dataset yield a different and more orthodox result: Archaeopteryx is restored as a basal bird with bootstrap ... origin of typical (forelimb-powered) bird flight. The Archaeopteryx –deinonychosaur clade retrieved by parsimony is supported by ... which are on average more homoplasious), whereas the Archaeopteryx –bird clade retrieved by likelihood-based methods is ...

Tópico(s): Morphological variations and asymmetry

2011 - Royal Society | Biology Letters

Artigo Acesso aberto Revisado por pares

Gregory M. Erickson, Oliver W. M. Rauhut, Zhonghe Zhou, Alan H. Turner, Brian D. Inouye, Dongyu Hu, Mark A. Norell,

Background Archaeopteryx is the oldest and most primitive known bird (Avialae). It is believed that the growth and energetic physiology of basalmost birds such as Archaeopteryx were inherited in their entirety from non-avialan ... avialan dinosaurs. Methodology/Principal Findings We report that Archaeopteryx long bones are composed of nearly avascular parallel- ... of a scale-dependent maniraptoran histological continuum that Archaeopteryx and other basalmost birds follow. Growth analysis for Archaeopteryx suggests that these animals showed exponential growth rates ...

Tópico(s): Morphological variations and asymmetry

2009 - Public Library of Science | PLoS ONE

Revisão Revisado por pares

John H. Ostrom,

Reexamination of the specimens of Archaeopteryx, which constitute the only direct evidence pertaining to the habits and mode of life of the earliest stages of avian evolution, ... the origin of avian flight. The osteology of Archaeopteryx, in virtually every detail, is indistinguishable from that ... reflect a highly predaceous mode of life for Archaeopteryx, rather than being arboreal adaptations. Plumage, in the ... primaries" and "secondaries" transformed the forelimbs of "proto-Archaeopteryx" into large, continous, trapping surfaces-natural insect nets- ...

Tópico(s): Avian ecology and behavior

1974 - University of Chicago Press | The Quarterly Review of Biology

Artigo Acesso aberto Revisado por pares

Christian Foth, Oliver W. M. Rauhut,

Archaeopteryx is an iconic fossil that has long been pivotal for our understanding of the origin of ... Germany. Twelve skeletal specimens are reported so far. Archaeopteryx was long the only pre-Cretaceous paravian theropod ... known clade of avialan, here named Anchiornithidae. However, Archaeopteryx remains the only Jurassic paravian theropod based on ... outside China.Re-examination of the incomplete Haarlem Archaeopteryx specimen did not find any diagnostic features of ... the specimen markedly differs in proportions from other Archaeopteryx specimens and shares two distinct characters with anchiornithids. ...

Tópico(s): Ichthyology and Marine Biology

2017 - Springer Science+Business Media | BMC Evolutionary Biology

Artigo Acesso aberto Revisado por pares

Uwe Bergmann, R. W. Morton, Phillip L. Manning, William I. Sellers, Sophie Farrar, K. G. Huntley, Roy A. Wogelius, P. L. Larson,

... avian characters, such as feathers, as seen in Archaeopteryx from the Solnhofen limestone. These rare fossils were ... has, until now, never been completed on any Archaeopteryx specimen. Here we present chemical imaging via synchrotron ... X-ray fluorescence (SRS-XRF) of the Thermopolis Archaeopteryx , which shows that portions of the feathers are ... in bone. Other previously unknown chemical details of Archaeopteryx are also revealed in this study including: bone ... of the life chemistry and fossilization processes of Archaeopteryx and other extinct organisms because it is now ...

Tópico(s): Evolution and Paleontology Studies

2010 - National Academy of Sciences | Proceedings of the National Academy of Sciences

Artigo Revisado por pares

JI Shu'an, Qiang Ji,

Abstract: Jinfengopteryx is a newly uncovered Archaeopteryx ‐like avialan bird outside Germany, which was found from the Jehol Biota of northern Hebei in northeastern China. It shares many characters only with Archaeopteryx by the possession of three fenestrae in the ... indicate Jinfengopteryx is even slightly more primitive than Archaeopteryx , although both birds can be placed at the ... suggested to be slightly more advanced than Jinfengopteryx + Archaeopteryx , supported by some derived features in teeth, shoulder ...

Tópico(s): Evolution and Paleontology Studies

2007 - Wiley | Acta Geologica Sinica - English Edition

Artigo Acesso aberto Revisado por pares

Per Christiansen, Niels Bonde,

The feathers of Archaeopteryx have been known for over 140 years, are the most important reason for its fame and avian status. Previous ... were mechanically removed appear unsubstantiated. Rather, the Berlin Archaeopteryx has to this day the same regions more ... 3 (2004). Plumage sur le corps de l'Archæopteryx : une revue et nouvelles indications fournies par le spécimen de Berlin. Les plumes d'Archaeopteryx sont connues depuis 140 ans, la raison la ... mais enlevées mécaniquement apparaissent dénuées de fondement. L'Archaeopteryx de Berlin a, à ce jour, ces mêmes ...

Tópico(s): Animal Behavior and Reproduction

2004 - Elsevier BV | Comptes Rendus Palevol

Artigo Acesso aberto Revisado por pares

Patricio Domínguez Alonso, Angela C. Milner, Richard A. Ketcham, M. J. Cookson, Timothy B. Rowe,

Archaeopteryx, the earliest known flying bird (avialan) from the Late Jurassic period, exhibits many shared primitive characters ... a long bony tail and pinnate feathers2. However, Archaeopteryx possessed asymmetrical flight feathers on its wings and ... of the braincase of the London specimen of Archaeopteryx. Here we show the reconstruction of the braincase ... the brain and inner ear. These suggest that Archaeopteryx closely resembled modern birds in the dominance of ... sensory perception in the ear. We conclude that Archaeopteryx had acquired the derived neurological and structural adaptations ...

Tópico(s): Evolution and Paleontology Studies

2004 - Nature Portfolio | Nature

Artigo Revisado por pares

Andrzej Elżanowski, Peter Wellnhofer,

... bones are preserved in the seventh skeleton of Archaeopteryx. Whereas most of the braincase bones and the ... the predominantly reptilian postcranial skeleton, the skull of Archaeopteryx shows a few specifically avian traits. The palatine ... the avian features of the skull demonstrate that Archaeopteryx is a bird rather than a feathered nonavian ... of the squamosal add to the evidence that Archaeopteryx is the most primitive of the unquestionable birds known to date. Archaeopteryx is more like certain theropods than any other ...

Tópico(s): Ichthyology and Marine Biology

1996 - Taylor & Francis | Journal of Vertebrate Paleontology

Artigo Acesso aberto Revisado por pares

Dennis F. A. E. Voeten, Jorge Cubo, Emmanuel de Margerie, Martin Röper, Vincent Beyrand, Stanislav Bureš, Paul Tafforeau, Sophie Sanchez,

Archaeopteryx is an iconic fossil taxon with feathered wings from the Late Jurassic of Germany that occupies ... context. Here, we compare new data from three Archaeopteryx specimens obtained through phase-contrast synchrotron microtomography to ... strategies. Our analyses reveal that the architecture of Archaeopteryx's wing bones consistently exhibits a combination of ... utilising short-distance flapping. We therefore interpret that Archaeopteryx actively employed wing flapping to take to the ...

Tópico(s): Amphibian and Reptile Biology

2018 - Nature Portfolio | Nature Communications

Artigo Acesso aberto Revisado por pares

Ryan M. Carney, Jakob Vinther, Matthew D. Shawkey, Liliana D’Alba, Jörg Ackermann,

Archaeopteryx has been regarded as an icon of evolution ever since its discovery from the Late Jurassic ... we report the first evidence of colour from Archaeopteryx based on fossilized colour-imparting melanosomes discovered in ... morphology predicts that the original colour of this Archaeopteryx feather was black, with 95% probability. Furthermore, reexamination ... melanization would have provided structural advantages to the Archaeopteryx wing feather during this early evolutionary stage of ...

Tópico(s): Amphibian and Reptile Biology

2012 - Nature Portfolio | Nature Communications

Artigo Revisado por pares

Andrzej Elżanowski,

The Solnhofen (Sixth) specimen of Archaeopteryx is assigned to Wellnhoferia grandis gen. et sp. n. on the basis of qualitative, size-independent autapomorphies. Wellnhoferia differs from Archaeopteryx in a short tail with the estimated number ... length and digit IV substantially shorter than in Archaeopteryx; and the number of four (instead of five) ... suggests a locomotor specialization different from that of Archaeopteryx.

Tópico(s): Ichthyology and Marine Biology

2001 - Institute of Paleobiology | Acta Palaeontologica Polonica

Artigo Acesso aberto Revisado por pares

Per Christiansen, Niels Bonde,

... of its discovery in 1860 to this day Archaeopteryx has been essential to our understanding of avian ... Gauthier 1986) taxa discovered within the last decade, Archaeopteryx remains the most basal avialan taxon. A very ... the bones. This has previously been reported in Archaeopteryx as well, in the cervical vertebrae of the ... present in modern birds were also present in Archaeopteryx. Evidence of pubic pneumaticity was also found in ...

Tópico(s): Evolution and Paleontology Studies

2000 - Royal Society | Proceedings of the Royal Society B Biological Sciences

Artigo Revisado por pares

Stephen M. Gatesy, Kenneth P. Dial,

... birds have extremely short tail skeletons relative to Archaeopteryx and nonavialian theropod dinosaurs. Long- and short-tailed ... making up the flight surface: frond shaped in Archaeopteryx and fan shaped in extant fliers. Mechanisms of ... by the remaining caudal muscles. The tail of Archaeopteryx, however, differs from this arrangement in several important respects. Archaeopteryx probably had a limited range of lift forces ...

Tópico(s): Avian ecology and behavior

1996 - Oxford University Press | Evolution

Artigo Revisado por pares

Max K. Hecht, Samuel F. Tarsitano,

Several theories of relationships of Archaeopteryx are discussed and it is concluded that the closest relatives in the taxon Thecodontia. Based on the morphology it is suggested ... tetrapod and no intermediate bipedal stage was required. Archaeopteryx was probably an accomplished glider with some powered ... a scavenger. Plusieurs théories sur les affinités d'Archaeopteryx sont examinées, et on conclut que ses plus ... pas nécessaire de postuler un stade bipède intermédiaire. Archaeopteryx était probablement un bon planeur, avec quelques possibilités ...

Tópico(s): Ichthyology and Marine Biology

1982 - Elsevier BV | Geobios

Artigo Revisado por pares

Brian O’Farrell, John Davenport, Thomas H. Kelly,

IbisVolume 144, Issue 4 p. 686-688 Was Archaeopteryx a wing-in-ground effect flier? Brian O' ... wig/html/aerodynamics.html. De Beer, G. 1954. Archaeopteryx Lithographica. London: British Museum Natural History. Bennett, A. ... 476. Feduccia, A. & Tordoff, H. 1979. Feathers of Archaeopteryx: asymmetric vanes indicate aerodynamic function. Science 203: 1021– ... com/wig/theory/stability.html. Ostrom, J. 1974. Archaeopteryx and the origin of flight. Quart. Rev. Biol. ... The Beginnings of Birds. Proceedings of the International Archaeopteryx Conference Eichstätt 1984 : 233–242. Willibadsburg: Freunde des ...

Tópico(s): Insect and Arachnid Ecology and Behavior

2002 - Wiley | Ibis

Artigo Acesso aberto Revisado por pares

Robert L. Nudds,

... it was proposed that the primary feathers of Archaeopteryx lithographica (HMN1880) were overlaid by long covert feathers, ... feathered forelimbs. The proposed long covert feathers of Archaeopteryx were previously interpreted as dorsally displaced remiges or ... premature to conclude unequivocally that the wing of Archaeopteryx consisted of primary feathers overlaid with elongated coverts.

Tópico(s): Ichthyology and Marine Biology

2014 - Public Library of Science | PLoS ONE

Artigo Acesso aberto Revisado por pares

Thomas G. Kaye, Michael Pittman, Gérald Mayr, Daniela Schwarz, Xing Xu,

... was described as the holotype of the iconic Archaeopteryx lithographica . The isolated feather’s identification has been ... as a primary, secondary or tail feather of Archaeopteryx . However, it could be a covert or a ... since the latter are not well known in Archaeopteryx . The possibility remains that it stems from a ...

Tópico(s): Optical measurement and interference techniques

2019 - Nature Portfolio | Scientific Reports

Artigo Acesso aberto Revisado por pares

Xing Xu, Diego Pol,

... methods were applied to the same dataset, restoring Archaeopteryx to basal Avialae, suggesting these methods should be ... for different phylogenetic hypotheses. Our analysis demonstrates that Archaeopteryx represents a challenging taxon to place in the ... provide increased support for the deinonychosaurian affinities of Archaeopteryx. Most importantly, we underscore that methodological choices should ...

Tópico(s): Morphological variations and asymmetry

2013 - Taylor & Francis | Journal of Systematic Palaeontology

Artigo Revisado por pares

Peter Wellnhofer,

Abstract Archaeopteryx , first discovered in 1861 from the Solnhofen lithographic limestone of Bavaria, is the oldest feathered animal in ... a dinosaurian ancestry for birds based on more Archaeopteryx specimens and new discoveries of theropod dinosaurs. Finally, ... advent of cladistic methodology was instrumental in supporting Archaeopteryx and Aves within the theropod clade Maniraptora, a ...

Tópico(s): Amphibian and Reptile Biology

2010 - Geological Society of London | Geological Society London Special Publications

Artigo Revisado por pares

Nicholas R. Longrich,

... the morphology and function of hindlimb plumage in Archaeopteryx lithographica. Feathers cover the legs of the Berlin ... hindlimbs acted as airfoils. A new reconstruction of Archaeopteryx is presented, in which the hindlimbs form approximately ... Presence of the “four-winged” planform in both Archaeopteryx and basal Dromaeosauridae indicates that their common ancestor ...

Tópico(s): Avian ecology and behavior

2006 - Cambridge University Press | Paleobiology